A number of toners may, in some situations, lack the ability to permanently remain on a medium after printing, for example in a printing or xerographic process. It is especially important for an image printed on a material to be used in packaging or mailing to be permanent, as packages are frequently bent and twisted and subjected to rubbing.
In electrostatographic imaging, electrostatic latent images are formed on a surface by uniformly charging a charge retentive surface, such as a photoreceptor. The charged area is then selectively dissipated in a pattern of activating radiation corresponding to the original image. The latent charge pattern remaining on the surface corresponds to the area not exposed by radiation. Next, the latent charge pattern is visualized by passing the photoreceptor past one or more developer housings comprising toner, which adheres to the charge pattern by electrostatic attraction. The developed image is then fixed to the imaging surface or is transferred to a receiving substrate, such as paper, to which it is fixed by a suitable fusing technique, resulting in a xerographic print or toner-based print. Once an image is printed, an overcoat varnish may be placed over the image in accordance with aspects of the disclosure illustrated herein.